Gas burner



March 14, 1944. B. K. G. EHNBOM GAS BURNER Filed May 2, 1940 I INVE TOR.

I BY

Bo Karl George Elmbom, Stockholm, Sweden, as-

signor, by mesne assignments, to Servel, 1:10., New York, N. Y., acorporation of Delaware Application May 2, 1940, Serial No. 332,928

In Germany June 20, 1939 3 Claims. (c1. 158-99) My invention relates togas burners, and more especially to a gas burner suitable for burningcomparatively small quantities of gas having a.

high hydrocarbon content. Inthe ordinary gas burner, such as a Bunsenburner, the gas issues,

froma jet which creates a suction effect capable of drawing insuflicient air to produce a combustible mixture within the tube of theburner. Such a device is suitable for burning gas having the ordinaryhydrocarbon content, inasmuch as the suction efiect draws in sufilcientair to produce complete combustion. However, certain natural gases havesuch a high hydrocarbon con-- tent, and consequently require so much airfor complete combustion, that the suction effect of the gas jet is notsuflicient. This is particularly so when a comparatively small flame isdesired, as for instance in a domestic gas heated absorptionrefrigerating apparatus.

In accordance with my invention I provide a gas burner suitable forproducing complete combustion of comparatively small quantities of highhydrocarbon content gas. Further objects and advantages of my inventionwill be apparent from the following description, considered inconnection with the accompanying drawing, which forms a part of thisspecification and of which the single figure is a cross-sectional viewof an embodiment'of my invention.

Referring to the drawing, reference character in designates a gas supplyconduit, the outlet of which is provided with a jet II. Secured toconduit Ill around jet II is an elongated member l2 having an enlargedlower portion l3 connected to or integral with a Venturi shaped\tube I4hav-.

ing a throat l5 and a mixing chamber IS. The enlarged portion l3is'iormed with one or more openings 24 communicating with theatmosphere.

The upper end of tube I4 is provided with exterior threads 35 forengagement with similar threads formed on a. collar 36, to which issecured the burner head 31. The head is preferably made of refractorymaterial and includes a solid top wall 38 and a cylindrical side wall 39formed with an internal shoulder 4B.

4| is provided with a plurality of comparatively long and narrowpassages 44 which communicate with the interior of the burner headbeyond the passage 43. Member 4| is also formed with one or moreopenings or ports 45 which communicate with the interior of the burnerhead between the upper end of tube 14 and the passage 43.

A skirt 46 is disposed around the primary air openings 24 in order toeliminate or minimize the effect ot-air currents.

The operation of the burner illustrated and described above is asfollows:

Gas is discharged from the jet l I and resulting suction eflect drawsprimary air in through the openings 24. This gas and air mix in theprimary mixing chamber l6 and flow into member 4|. From here the mixturepasses partly through the openings 44 and partly through the openings 45into the secondary air mixing chamber 23 within the burner head 31. Theair and gas mixture passes from the chamber 23 through the openings 22,while at the same time secondary air enters the chamber 23 through thesesame openmgs. flows through the upper part of each opening and thesecondary air enters through the lower part,

probably largely as aresult of eddy currents. The introduction of thissecondary air supplies the necessary amount of oxygen required toproduce complete combustion 01 a high hydrocarbon content gas. As shownin the drawing, the arrangement of the openings 22 is such thatsummon-shaped flame is produced, which is desirable for heating thegenerator or heat receiving part of a refri erating apparatus.

The annular passage 43, constitutes, in effect, a by-pass around thepassages 44. Consequent- 1y, increasing the area of annular passage 43decreases the resistance to flow from the primary air mixing chamber I6to the secondaryair mixing chamber 23, thereby increasing the suctionef- A hollow member 4!, preferably of refractory providing anannularpassage 43, the cross-sectional area of which may be varied by screwingthe collar 36 up or downon the end oi. tube I2,-

thus increasing or decreasing respectively, the

area of the pa "sage. The upper end of-member material, is secured tothe upper end of tube 14 fect produced by the jet ll. Thus, by adjustingthe collar 36 on the tube l2 to vary the crosssectional area of thepassage 43, the quantity of primary air may be regulated to obtaincomplete combustion with. gases having diflerent hydrocarbon content.

It will thus be seen that, in accordance with my invention, I haveprovided a very simple bumer suitable for burning small quantities oi.high hydrocarbon content gaseous fuels.

What is claimed:

1. A gas burner including structure forming a first mixing chamber, anozzle projecting into said The air and gas mixture, being lighter,

chamber, the nozzle being provided with a ms- "sage terminating in adischarge orifice from which gas is discharged into said chamber, saidstructure having openings to permit flow of air into said chamber to mixwith gas therein, a burner head mounted on said structure and forming thside and top walls of a second chamber,

' and a wall member separating said first and second chambers and havingopenings which are wall member, and said structure having portsproviding communication for said first chamber with said annular passageadjacent said wall member so that the gas mixture may flow to thesecond, chamber from the first chamber both through said openings in thewall member and also through said ports and said annular passage,and-said burner head having openings therein for admitting secondary airinto said second chamber to increase the proportion of air in the gasmixture therein and for discharging the gas mixture therefrom, theburner head being formed of refractory material and having the outersurface thereof serving as the region where the burner flame is producedand maintained.

i. A gas burner as set forth in claim 1 in which said burner head ismovable with respect to said structure-,- and said head and saidstructure are so formed and arran ed that movement of said head causes avariation in a cross-sectional area 'of said annular space,

3. A gas burner including structure forming a first mixing chamberhaving gas and air inlets, said structure including a wall member havingopenings therethrough for permitting flow of the mixture of gas and airfrom said first chamber, a burner head secured to said structure andproviding the side and top walls of a second mixing chamber whichreceives the mixture of air and gas from said first chamber through theopenings in said wall member, the openings in said wall member beingmaterially greater in length than in diameter, said wall member havingone or more ports for the "mixture of air and gas from said firstchamber to said second chamber without passing through the openings insaid wall member, said head having flame ports in said side wall, and

said top wall being imperforate to baille flow of combustible mixture inthe line openings in said wall member.

KARL GEORGE EHINBOM.

of theaxis of the to provide a path of flow.

